18. Mazama Deposits: a jewel born of destruction

Just 7,700 years ago, Mount Mazama, an active, 12,000-foot tall High Cascade volcano, exploded in a massive eruption that blew 50 cubic miles of rock and ash into the air. The eruption blanketed the surrounding landscape with red-hot flows of ash and pumice and produced a cloud of ash that rained down over an area covering eight western states and three Canadian provinces. What was left of the volcano collapsed on itself, leaving a gaping hole that subsequently filled with snow melt to form Oregon’s iconic Crater Lake, today Oregon’s only national park. The amount of material erupted would cover the entire state to a depth of almost three feet.

OGDC units: includes all mapped Holocene air fall and ash flow deposits from the climatic Mazama eruption